Electric accumulator



K. W. J. HJELMBLD ELECTRIC ACGUMUATOR Filed March 16, 1933 Patented May 26, 1936 Y ilbii STES P A T E T GFFIQE ELECTRIC ACCUMULATOR Application March 16,

1933, Serial No. 661,341

In Sweden March 17, 1932 2 Claims.

It is known to make accumulators from socalled envelopes lled with active substance, said envelopes being' fixed to frame rods of conducting material, which in their turn are connected to common bus-bars or pole bolts for instance by means of connecting lugs.

'Ihe known construction of this kind have the drawbacks that, as time goes on, the electric contact between the envelopes and the frames becomes unsatisfactory, that the active substance is pressed from the envelopes due to changes of volume when working.

The invention is illustrated in the accompanying drawing, in which Fig. 1 is a fragmentary front elevation of a group of accumulator plates fixed to the frame.

Fig. 2 is a section along the line 2 2 of Fig. 1.

Figs. 3, 4 and 5 are corresponding sections 0f other embodiments.

Fig. 6 is a cross section on the line 6 6 of Fig. 1.

According to the invention the device for securing the envelopes I to the frame rods is considerably improved. In the device according to Fig. 2 the frame rods 2 consist of a metal band,

which presents in cross section two side legs I5 having their inner ends bent apart and connected by a flat base portion It, the outer ends I8 of the side legs being folded back. In the frame rods 2 there are transverse slits I9 in which the edges 2Q of the ends of the envelopes are inserted. The outermost portions 2l of the edges 2U are fixed between the non-folded medial portions of the legs and their folded portions I8. Thus a good foulhold contact surface is obtained at each of the ends of the envelopes, which is of a very great importance for securing a reliable current transition; The flat Ibase portion II of the frame portion serves to retain the active substance 22 in the envelope. Due to the fact that some intermediate space is left between the base portion I5 and the legs the active substance has the possibility of extending. In Figs. 3, 4 and 5, some modifications of frame rods are shown. The modification according to Fig. 3 differs from the one according to Fig. 2 only therein that between the two portions I5 there is inserted a bar Zfi, which is fixed to the legs by means of welding or by rivets 25. It is often suitable to use welding instead of rivets. In the devices according to Figs. 4 and 5 the base (Cl. 13G-43) portion I5 according to Figs. 2 and 3 is omitted, but the ends 26 of the legs are bent outward as in Fig. 2. The shape of the base portion and the rest of the interior portion of the legs is, however, unessential for the invention.

If the envelopes have a round cross section the slits I9 are cut so that the base portion I5 and the outwardly bent portionsv of the legs respectively correspond to the interior cross section of the envelopes, which are then often flattened a little at the ends.

Each envelope I containing the active substance consists of a single metal band, which is so folded in its longitudinal direction, that the cross section substantially forms a rectangle. According to the invention the lap 2l for closing the `envelope is disposed at one corner of the rectangle, and extends some way on one short side, the other short side 28 being sunk so that it leaves a space for the lap of the adjacent envelope, and locks the said lap, and close to the same leaves an intermediate space 28 between the envelopes.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In an electric accumulator, envelopes filled with active substance and each having two adjacent spaced edges, frame rods, said frame rods including leg members having the medial portions thereof located between said edges, certain ends of the leg members contacting and terminating within the envelopes and 'being bent apart, and the opposite integral ends of each leg mem'- ber being folded back against and in contact with the external surface of the adjacent edge portion.

2. In an electric accumulator, envelopes filled with active substance and each having two adjacent spaced edges, frame rods, said frame rods including leg members having the medial portions thereof located between said edges, certain ends of the leg members contacting and terminating within the envelopes and being bent apart, and the opposite integral ends of each leg member being folded back against and in contact With the external surface of the adjacent edge portion, and a base member located within each envelope and connecting the rst mentioned ends of the leg members.

KARL WILHELM JOSEF HJELMBLAD. 

